The goal of this project is to continue to study the interrelationships of cell membranes involved in the transport and discharge of secretory proteins in the pancreatic acinar cell and to examine the properties of the plasmalemma as they related to stimulus-secretion coupling, embryonic morphogenesis, and neoplastic transformation. Specific goals include: (1) Synthesis of photoactivatable, radiolabeled octapeptide analogs of pancreozymin for studies on secretagogue receptor biochemistry and cellular localization; (2) Isolation of the apical and basolateral plasmalemma with biochemical studies of their role in exocytosis; (3) Studies on the distribution and function of cell surface glycoproteins in pancreatic morphogenesis; and (4) Examination of the properties of the plasmalemma of a differentiated pancreatic acinar cell tumor and a comparison of these properties both with the normal acinar cell and with the developing embryonic pancreatic rudiment.